added Parsing instrucctions

doc/tabellen/sample_table_nd.xml

@@ -85,6 +85,22 @@
                 <dcc:content lang="de">Fläche mit Indexvektoren</dcc:content>
                 <dcc:content lang="en">Surface Area with Index Vectors</dcc:content>
               </dcc:name>
+              <dcc:description>
+              <dcc:content refType="parsing_parsingInstrutions">
+                Data Readout Instructions:
+                1. The 2D measurement data is stored in a flattened array (C-style row-major) under refType="basic_FlattTableData".
+                2. Two index vectors are stored under refType="basic_FlattTableIndices":
+                   • Outer index: refType="basic_FlattTableIndex1"
+                   • Inner index: refType="basic_FlattTableIndex2"
+                3. Total datapoints = (number of outer indices) × (number of inner indices).
+                4. To map a flat index to 2D coordinates (using 0-based indexing):
+                     Index(outer, inner) = outer × (length of inner index) + inner.
+                5. Example Test Data:
+                     • Values: {(2,9): 3.55, (7,3): 8.17}
+                     • Uncertainties: {(2,9): 0.07938, (7,3): 0.18269}
+              </dcc:content>
+
+              </dcc:description>
               <dcc:list refType="basic_FlattTableIndices">
               <dcc:name>
                 <dcc:content lang="de">Indexvektoren</dcc:content>